Machine for producing a three dimensional lattice

ABSTRACT

A machine for making a three dimensional lattice array of strands within a grid framework. The strand lattice can be utilized as a reinforcement for other materials.

United States Patent 11 1 Amos July 29, 1975 1 MACHINE FOR PRODUCING ATHREE [56] References Cited DIMENSIONAL LATTICE UNITED STATES PATENTS[75] I entor; Homer C, Amos, Palm Springs, 1,949,148 2/1934 Dl'Oll et a1112/3 A Calif. 2,089,252 8/1937 Droll et al.... 112/3 A 2,098,78511/1937 Mathewson 112/3 A [73] Assignee: Brunswick Corporation, Skokie,111. 2,737,230 4/1957 112/3 A Filed y 6 1974 2,920,588 1/1960 Bronsteinet al 112/3 A [21] Appl. No.: 466,974 Primary Examiner-Alfred R. GuestAttorney, Agent, or Firm-John G. Heimovics; Donald Related U.S.Appllcatlon Data S olexa; S. L. Epstein [62] Division of Ser. No.272,736, July 18, 1972, Pat. No.

33221461 57 ABSTRACT A machine for making a three dimensional lattice1122'1123A,112 121.23

(5 2 l 23/00 array of strands w1th1n a gr1d framework. The strand [58] i3 A 121.15 lattice can be utilized as a reinforcement for othermaterials.

30 Claims, 25 Drawing Figures MENTEB W SHEET MACHINE FOR PRODUCING ATHREE DIMENSIONAL LATTICE This application is a divisional applicationof my copending appication, Ser. No. 272,736, filed July 18, 1972 nowissued as US. Pat. No. 3,822,463 on July 9, 1974.

FIELD OF THE INVENTION This invention relates to strand lacing machines,and more particularly, to sewing machines capable of making a threedimensional lattice array of strands.

BACKGROUND OF THE INVENTION Many material forms are used today ascomposite materials in order to take advantage of the best properties ofthe different materials forming the composite. Fabric reinforced plasticresins are one class of such composite materials in wide use.Complicated designs have been employed to utilize the two dimensionallimitations of the fabric in order to produce three dimensional shapes.There are many problems in producing a three dimensional shape from atwo dimensionally reinforced material; for example, a laminated glassfabric-plastic resin composite can delaminate just like paint peelingoff a house because the composite is not reinforced in all threedimensions. Thus, the obvious need for three dimensionally reinforcedcomposite materials exists.

In order to provide a three dimensionally reinforced product, it isfirst necessary to provide a lattice of strands or yarns in a threedimensional array. One attempt to make such a three dimensional strandarray is taught in US. Pat. No. 3,322,868, wherein two rather crudedevices are used in combination. The first device provides a pluralityof parallel strands on a structure similar to a picture frame. Multipleframes are then alternately stacked to provide groups of strands thatare perpendicular to each other. A second device having a plurality ofsemi-conductor pointed needles, each having a single strand or yarn, isused in conjunction with positioning rods to lace the strands of theframes in only the third dimension. These two devices require a greatdeal of hand operation to provide an awkward lattice array that (1) doesnot have uniform or preselected pretensioning of the strands; (2) isunreliable to provide reproducibility in lattice arrays; (3) is lackingin uniformity; and, (4) is uneconomical to use.

SUMMARY OF THE INVENTION The invention contemplated and disclosed hereinprovides a new, novel and unique sewing machine that produces asubstantially uniformly prestressed three dimensional strand latticethat has the attributes of being reliable, reproducible, uniform,economical and achieves solutions to the problems that the prior art hasleft unsolved. Such a machine utilizes new and novel sewing machineswhich operate in conjunction with a new and novel grid frameworkstructure that supports the strands.

Therefore, it is an object of this invention to provide a threedimensional lattice array of strands made automatically andeconomically.

Another object of this invention is the provision for producing alattice whereby each strand has substantially the same tension as everyother strand in the lattice.

Still another object of this invention is the provision for producing athree dimensional lattice array of strands wherein the strands are in asubstantially orthogonal configuration.

Yet another object of this invention is the provision for an open gridframework structure that can have a three dimensional array ofsubstantially equally tensioned strands sewn therein.

And still another object of this invention is the provision for a newtype of sewing needle.

Still yet another object of this invention is to provide a method formaking a three dimensional lattice array of strands in an open gridframework structure.

A feature of the invention is the provision for a needle that sews aplurality of threads.

Another feature of the invention is the provision for a grid frameworkstructure wherein very fine flexible strands support the sides of thegrid box.

Yet another feature of this invention is the provision for rigid and/orflexible hooks that secure the strands to the grid box.

Still another feature of the invention is the provision forsubstantially equally tensioning a plurality of strands that are sewn bysuch a machine using only a single tensioning device.

And still another feature of the invention is the provision for meansthat secure the sides of the grid surfaces to form a grid structure boxand also provide for uniformly feeding the grid box in the machine.

A structural grid box formed with open grid surfaces is placed onto thetable of the machine. A strand attaching means or clip is used to fastenall the strands or yarns to the grid box; the strands coming from theplurality of needles secured to the machine. The grid box is placed inposition with respect to the needles at the start of the operation.During operation, the needles moving forward enter the openings in thegrid box sewing the strands that are secured to the grid surfaceopposite to where the needles enter, and then the needles are withdrawnfrom the grid box which is automatically advanced with the sewing cyclerepeated. When the sewing operation in one direction is completed, thestrands are fastened to the grid box and cut therefrom. The grid box isrepositioned on the machine in a second orientation and then a thirdorientation so that sewing of the second and third directions may takeplace in a manner similar to that of the first direction. Thus, uponcompletion, the grid box contains a three dimensional lattice array ofstrands.

The above and further objects and features will be more readilyunderstood by the reference to the following detailed description andthe accompanying drawmgs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial end elevation viewof part of the machine portion of one embodiment of the invention;

FIG. 2 is a partial side elevation view of part of the machine portionof one embodiment of the invention;

FIG. 3 is a partial side elevation view of the feeding device for thestrand holding means of one embodiment of the invention;

FIG. 4 is a partial side elevation view of the strand guide and strandtensioning device portion of the invention;

FIG. 5 is a partial end elevation view of the strand guide of theinvention;

FIG. 6 is a segmented view of one part of the grid box portion of oneembodiment of the invention;

FIG. 7 is a cross sectional segment view of a portion of the grid box onthe feed table in contact with the feeding device of one embodiment ofthe invention;

FIG. 8 is a perspective view of an assembled grid box of one embodimentof the invention;

FIG. 9 is a partial sectional view of the driving mechanism for thefeeding device portion of one embodiment of the invention;

FIG. 10 is a perspective view of a corner bracket for the grid boxportion of one embodiment of the invention;

FIG. 11 is a side elevation view of a corner bracket of the grid boxportion of one embodiment of the invention;

FIG. 12 is a side elevation view of a corner of a grid box wall of oneembodiment of the invention;

FIG. 13 is a segmented cross section view of one grid box surface of oneembodiment of the invention;

FIG. 13a is a segmented cross section view of a portion of one grid boxsurface and needles of one embodiment of the invention;

FIG. 14 is a segmented cross section view of a portion of one grid boxsurface of one embodiment of the invention;

FIG. 15 is a cut away perspective view of one embodiment of theinvention;

FIG. 16 is a segmented cross section view of a portion of one embodimentof the invention;

FIG. 17 is a segmented cross section view of a portion of one embodimentof the invention;

FIG. 18 is a perspective view of the needle point of one embodiment ofthe invention;

FIG. 19 is a segmented cross section view of one grid surface and theneedles during the sewing of one grid of one embodiment of theinvention;

FIG. 20 is a segmented cross section view of one grid surface and theneedles wherein the sewing has progressed farther than FIG. 19 anddepicting one embodiment of the invention;

FIG. 21 is a segmented cross section view of one grid surface and theneedle wherein the sewing has progressed farther than FIG. 20 anddepicting one embodiment of the invention;

FIG. 22 is a segmented cross section view of one grid surface and theneedles on the upstroke of one embodiment of the invention;

FIG. 23 is a perspective view of another embodiment of the invention;and

FIG. 24 is a segmented cross sectional view of the needle and the uppergrid surface of one embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment, thebasic parts of the machine comprise a feed table having a feeding meansmounted thereon; a set of needles mounted on a slide that has areciprocating motion with respect to the table; and, a yarn or strandtensioning device that is cooperatively mounted with respect to theneedles. A necessary adjunct to the machine is a grid box comprisingforaminous grid surfaces with the box being held together by rods thatfunction cooperatively with the feeding to move the grid box through themachine in a preselected time sequence. The grid box is capable of beingfed into the machine and sewn by the needles; the box maintains thestrands in a three dimensional array. The needles and the strandtensioning device function to provide substantially equal tension in allthe strands during sewing.

As used herein, the term strand includes wire, thread, yarn,monofilament, cable, etc.; all are used inter changeably and arecontemplated to mean an elongated flexible element capable of being fedthrough the needles and the grid box to form a three dimensional latticearray.

In the operation of the machine, an assembled grid box is positioned onthe feed table with the starting ends of the strands or yarns secured tothe grid box such as by a yarn clip. The feeding means attached to thetable moves the grid box along the machine table in a preselected timesequence of move and dwell. During the dwell portion of the timesequence the needles with the strands of yarns therein enter the gridbox surface nearest thereto, passing into and through the grid box andjust past the far surface of the opposite grid box surface. The needleshave special points to cooperate with the strand holding means mountedon the far side grid surface in order to loop and secure the strandsthereto. After the threaded needle has been withdrawn from the grid box,the grid box is indexed to its next position and at the same time thestrands from the needles partially pass over the near side of the gridsurface. These strands are positioned by strand guides located on theexterior of the near side grid box surface. When the grid box has beenmoved to the next position, and during the dwell portion of the timingsequence, the needles again enter the grid box thereby completing thefirst sewing pass and starting the second sewing pass of the strands.This operation is repeated until the grid box is completely sewn in onedirection. The strands are secured to the grid box such as by a yarnclip and then cut, thus completingthe sewing operation in one direction,or for ease of understanding the X direction. The grid box is rotated onthe table and again fed into the machine. The strands are secured to theedge of the grid box and the grid box is, for a second time, indexedalong the feeding table with the needle sewing repeated. Upon completionof the sewing operation, the strands are again secured to the box andcut, completing the sewing in the second or Y direction. The gridstructure is then rotated for a second time on the grid table and fedthrough the machine with the strands sewn in the same fashion as before,thereby completing sewing in the third or Z direction. Thus, a threedimensional lattice array of strands completely fills the interior ofthe grid box. Since the grid box is a substantially rigid structure, theneedles operate in the same fashion during the total sewing operationand the strand tensioning device is mounted with the needles on theneedle mount to operate continuously and cooperatively; all partsfunction to insure that all strands are all substantially equallytensioned as they are sewn.

The invention also contemplates the method of making an open surfacegrid box having a three dimensional lattice array of strands internallycontained therein, with all strands substantially equally tensioned, bythe steps of the operation broadly described herein above. The basicsteps are feeding a grid box into the machine, sewing the strands withsubstantially equal tension throughout the grid box in three differentdirections, and securing the end of the strands to the grid box in orderto provide substantially equal tension on all the strands.

TI-IE GRID BOX In a preferred embodiment of the invention, a grid box500, shown in FIG. 8, comprises oppositely spaced foraminous grid walls510 and 520. The internal surfaces of the grid walls 510 and 520 areflat with the exterior surfaces providing hooks and notches for thestrands, as shown in FIG. 6. The grid walls 510 and 520 are used inpairs being oppositely spaced apart in forming the grid box 500. Thegrid walls 510 and 520 are of substantially rigid frameworks and may beformed of interlocking strips 511 and 512; and, 521 and 522 which definepassages 514 and 524 and the interior and exterior grid surfaces. Thestrips 511, 512, 521 and 522 have outwardly projecting undercut ends515, 516, 525 and 526, as shown in FIGS. 6, 7 and 12. On each of thestrips 512 of the grid wall 510 there are notches 518 to accommodate thepositioning of the strands during the sewing operation. On each of thestrips 521 of the grid wall 520 there are lugs 530 secured thereto. Thelugs 530 have ears 531 to provide a means for hooking the strands duringthe sewing operation. The tips 532 of the ears 531 are recessed withrespect to the exterior surface 520a of the grid wall 520, as shown inFIGS. 14, 15 and 16. The ears 531 of adjacent lugs 530 are spaced apartas shown in FIGS. 6 and 7. Corner brackets 540 with legs 541 are securedto each corner of the grid walls 510 and 520 where the undercut ends515, 516, 525 and 526 have been removed, as shown in FIGS. 6, 7, 8, 10,11 and 12. The dogs 542 of the corner brackets 540 are at an angle withrespect to the legs 541 and not in the same plane therewith; as shown inFIGS. and 11.

The grid box 500 is assembled by inserting undercut ends 515, 516, 525and 526 of the grid walls 510 and 520 into the undercut grooves 551 ofthe edge rods 550. In forming the grid box 500 the grid walls 510 and520 are positioned opposite to each other with the notches 518 and lug530 facing outwardly. A second series of grooves 552 on the rods 550 arealigned with the center of the grid passages 514 and 524. The threeadjacent dogs 542 of the corner brackets 540 are fastened together withsnap rings 543, as shown in FIGS. 6 and 8. The dogs 542 do not extendbeyond the edges formed by the rods 550. For proper operation, theopenings 514 and 524 must be aligned and the rows of lugs 530 must beparallel to the notches 518 when the surfaces are opposite each other.It is contemplated that the grid passages or openings 514 and 524 may besquare, rectangular, triangular, pentagonal, etc., as desired. Ratherthan forming the grid surfaces 510 and 520 by interlocking strips, it isfully contemplated that the grid surfaces may be cast or formed in anydesired manner.

It has been found necessary that the edge rods 550 form planar surfacesbut the grid surfaces 510 and 520 attached thereto do not necessarilyhave to be planar. The grid surfaces 510 and 520 can be any desiredshape as long as they do not extend beyond the planar surfaces definedby the edge rods 550.

Alternatively, resiliently flexible lugs 530a with car portions 531a, asshown in FIG. 16, may be used in place of the rigid lugs 530. Also, lug530b having movable ear portions 53lb may be used as shown in FIG. 17,wherein the ears 531b are mounted on shafts 532b which can rotate insuch a fashion to release the hooked strands.

The use of the assembled grid box 500 as it cooperatively functions withthe machine will be discussed hereinafter in more detail.

THE MACHINE In a preferred embodiment of the machine as shown in FIGS. 1and 2, the frame 10 supports a feed table 20 which is mounted thereon. Apair of upper slideways l3 and a pair of lower slideways 12 are mountedon and secured to the frame 10 in a space relation to the table 20. Theslideways l2 and 13 are shown covered with dust protectors 12a and 13a.Flywheel 30 is rotatably mounted on shaft 33 that is journal mounted 37on the frame 10 at 32. The flywheel 30 is located between the slideways12 and 13. The shaft 33 is connected to a prime mover, such as a motor(not shown) by means of sprockets and a chain (not shown), therebyproviding motion for the operation of the machine. A counterbalance 35is slideably mounted on the upper ways 13 and obtains reciprocatingmotion via the upper connecting rod 34 which is pivotally mounted on theflywheel 30 at 34a and on the counterbalance 35 at 3412. The needleholder is slideably mounted on the lower guideways 12 and pivotallyconnected to the flywheel 30 by the lower connecting rod 36 at 36a andto the needle holder 40 at 36b. As the flywheel 30 revolves, the needleholder 40 moves back and forth or upwards and downwards, as the case maybe, in a reciprocating motion. At the same time, the counterbalance 35moves in an opposite direction to the needle holder 40 to provide smoothand substantially vibrationless motion. A strand tensioning device ismounted on the needle holder 40 and operates to pull the multiplestrands from a strand or yarn creel (not shown) during both the upwardmotion of the holder 40.

The strands 700 enter through the strand guides 752 secured to the guideplate 751 that is part of the strand guide assembly 750 mounted on theframe 10 at 753, shown in FIGS. 4 and 5. The strands 700 passed underthe roll 754 and then passes up and over the dancer roll 704 that ispart of the strand tensioning assembly 50. The strand tensioningassembly 50 is mounted on the movable needle mount 40 while the strandguide assembly 750 is stationary. The dancer roll 704 is rotatablymounted on cantilevers 705 that are secured to the partially rotatablespring tensioned shaft 706. The spring 708 and the coupler 708a fastenedto shaft 706 tend to cause counterclockwise rotation thereof which inturn cause the dancer roll 704 to rotate in a counterclockwise directionaround the shaft 706. Cam 709 secured to shaft 706 and the cam keeper710 secured to the movable needle mount 40 insures only partialcounter-clockwise rotation of the shaft 706 and dancer roll 704.Clockwise rotation of the dancer roll 704 about the shaft 706 causes anincreased load on the spring 708 which functions to restrain suchrotation. As explained hereinafter, the semi-rotational confinement ofthe dancer roll 704 is what provides substantially equal tension on allthe strands as the lattice is formed.

The grid pusher assembly 210 is mounted at the side and underneath thefeed table 20, and driven by drive assembly 21 as shown in FIGS. 1, 2, 3and 9. Assembly 21 comprises pairs of bevelled gears at each end ofshaft 21a; one end thereof coupled to and being driven by the driveshaft 33 and the other end transferring the power for the grid pusherassembly 210. As shown in FIGS. 3 and 9, the grid pusher assembly 210has eccentric shaft 231 that is driven by the drive assembly 21 which iscoupled by timing and power transmission gears 233 to the cam shaft 232.Suitable journal bearings 234 are mounted on frame to support shafts 231and 232. Pusher arm 211 is eccentrically mounted on shaft 231 at 213. Atthe other end of the pusher arm 211 is a pawl 212 which reciprocativelymoves back and forth as the shaft 231 is rotated. The upward pusherassembly 220 is mounted on the frame 10 adjacent the pusher arm 21 1 andconnected thereto by coupler 227. Cam 221 is mounted on shaft 232 andengaged by cam follower 222 which is part of linkage 223 that ispivotally mounted on the frame 10 at 226 and pivotally connected to thecoupler 227 at 224. The coupler 227 is pivotally connected to the arm211 at 225. As cam shaft 232 rotates, the cam follower 222 imparts an upand down motion to the pusher arm 211 that is translated by the linkage223 in cooperation with the coupler 227. Thus, the combined motions fromthe eccentrically mounted pusher arm 221 and the cam follower 222coupled thereto cause the pawl 212 to rise above the top surface of thetable through hole 214; move forward; withdraw below the top surface ofthe table 20; oscillate back and forth; and, again rise above the topsurface of the table 20 pushing forward and withdrawing in a timedsequence of move and dwell. The amount of back and forth motion of thepawl 212 provides the incremental advance movement of the grid box 500along the feed table 20. When the grid box 500 with the edge rods 550 ispositioned on the feed table, the pawl 212 engages the groove 552 andfunctions to progressively indexedly advance the grid box 500 along thefeed table 20 in a preselected move and dwell time cycle sequence.Engagement of the pawl 212 in groove 552 of the rod 550 isshown in FIGS.3 and 7.

A friction brake 45, shown in FIGS. 1 and 2, is mounted on feed table 20and engages the sides of the grid box 500 to prevent overfeeding.However, other types of brakes are contemplated, such as a devicesimilar to the grid pusher assembly 210 but operating in a reversefashion to prevent the grid box 500 from moving during the dwellportion; and will be well understood by those skilled in the art.

A dual set of pressure rolls 70 is mounted on a framework 71 that isattached to the frame 10 and the feed table 20. One set of rollers 70 islocated in front of and just adjacent to needle 60 at the feed-insection of the machine on table 20. The second set of rollers 70 islocated between the needle 60 and the upright portion of the frame 10.Both sets of rollers are adjusted to a preselected height to create aslight pressure on the rod 550 of the grid box 500 as it isautomatically fed to the machine to prevent the grid box 500 fromlifting up from the table 20 during the sewing operation.

In another embodiment of the invention, the feed table can be slidablymounted on the frame and indexedly moved or advanced by a feeding devicesimilar to the grid pusher assembly 210. This would permit the grid boxto be secured to the feed table with both the table and the grid boxthereon advancing past the needle mount 40 during the reciprocatingmotion thereof.

Alternatively, in another embodiment of the invention, the grid box canbe secured to the table 20 and the needle mount slidably mounted on theframe 10 so that after every reciprocating motion thereof, the mount isadvanced with respect to the grid box by a feeding device similar to thegrid pusher assembly.

In yet another embodiment of the invention, it is contemplated that thegrid box can be mounted in such a manner as to be provided with aforward and back motion for sewing with the needles in the needle mountheld stationary. In this embodiment either the grid box or the needlemount can be slidably advanced. These order embodiments will be wellunderstood by those skilled in the art. All of these embodiments providerelative motion between the grid box and the needles to insure asatisfactory sewing operation of the total grid.

THE NEEDLES The butt or proximal ends 601 of the needle 60 are securedto the moveable needle mounts 40 with mounting brackets 610 as shown inFIG. 4. The point or distal end 602 of the needle 60 may be fashioned tosew one or more strands as shown in FIG. 18. The needle point.

602 has a rather sharply tapered side portion 606 converging at the tip614. Extending rearwardly toward the butt end 601 are undercut slots 604on both sides of the needle 60. The web 611 formed by the slot 604 mustbe thinner than the distance between the ears 531 of the lug 530.Gradually tapered top and bottom portions 606a of the point 602 form theother portions of the needle point 602 which converge at the tip 614.The slots 604 provide a flat portion 613 with a furthertaperedcurvilinear undercut portions 612 formed towards the tip 614. A taperedflat portion 609 is located between the tip 614 and the portion 612.Strand holes 603 open onto the portion 612 with the axis of the hole 603projecting rearwardly atany angle, and preferably 1 about a 30 angle.The holes 603 open on the bottom side 615 of the needle 60 which isactually the leading surface wherein the holes 603 cooperate with strandgrooves 608 that project rearwardly toward the butt end 601. On theupper side 616 of the point 602 are strand slot grooves 607 that projectrearwardly and intersect and cooperate with the slots 605. It has beenfound desirable to offset the holes 603 with respect to the slots 605wherein the slots 605 are closer to the sides 617 of the needle 60.During the forward stroke of the needle 60, the strand 700 is in aposition whereby it passes through the hole 603 and around the slot 605extending rearwardly in grooves 607 and 608.

OPERATION In making a three dimensional lattice array of strands,strands 700 from a creel are fed through the strand tensioning device 50as described hereinabove, and threaded through the needle holes 603,around the point 602 and back through the slots 605..An assembled gridbox 500 is placed on the feed table 20 so that.

the grid wall 510' with notches 518 is adjacent the needles 60 with theopposite grid wall 520 next to the table 20 with the ears 531 of thelugs 530 projecting towards the table. The needles 60 and the needlemount 40 are moved to a full upright, back or withdrawn position aboveor outside the grid box 500 and exterior to the grid wall 510, similarto FIG. 22. The strands 700 from the needles 60 are initially secured tothe grid wall 510 in the slot 560, as shown in FIG. 6, by the U-shapedspring clip (not shown). Alternatively, initial securing of the strandsto the box 500 may employ such simple means as taping the strands to thebox, or more sophisticated mechanical securing devices, well understoodby those skilled in the art.

The grid box 500 with strands 700 secured thereto is positioned on tableunder the first set of pressure holddown roller 70 in such a manner thatthe pawl 212 contacts the first of the series of rod 550 grooves 552.The brake 45 is clamped on the sides of the grid box 500.

The machine is started by the prime mover with the needles 60 alignedwith respect to entering the opening 514 of the grid surface 510. As theneedles enter the grid surface 510 the notches 518 align the strands700, as shown in FIG. 13a. As the needles 60 with the surface 615leading and the surface 616 trailing move through the grid surface 510toward the grid surface 520 the strands 700 are pulled by the needle 60motion and under substantially equal tension created by the dancer roll704 in cooperation with the spring tension shaft 706. As the doublestranded needles 60 pass through the openings 524 from the interior ofthe grid box 500, the strands 700 come into contact with the ears 531and are displaced inwardly from the holes 603 and the slots 605 towardthe web 61 l, as shown in FIG. 19. Near the end of the forward stroke ofthe machine, as the needles 60 continue to move through the openings 524of the grid wall 520 to a position where the needle holes 603 and theneedles slot 605 have cleared the ears 531, the strands 700 areautomatically pulled back to the normal position, as shown in FIG. 20.This return to the normal position occurs through the cooperative actionof the dancer roll 704 and the spring tension shaft 706. As the needles60 start on their backstroke to pull upward through the grid box 500,the strands 700 are hooked or looped on the undercut portions 533 of theears 531, as shown in FIG. 21. During the continued backstroke of theneedles 60, the strands 700 are pulled from the grooves 605 and remainin this position throughout the complete backstroke of the machine.Substantially equal tension is maintained on the strands during thebackstroke which is completed after the needles 60 have been withdrawnfrom the grid wall 510, as shown in FIG. 22.

After the needles 60 have been fully withdrawn from the grid wall 510 atthe upper end of the backstroke, the pawl 212 engages the next groove552 and indexes or pushes the grid box 500 forward to the next sewingposition; the grid box 500 is prevented from overfeeding by the brake45. During the advancing motion of the grid box 500 the notches 518align the strands 700 for the next sewing cycle. The forward motion ofthe needles 60 starts to repeat the sewing cycle, and the strands 700automatically align themselves in the needle slots 605 as a result ofthe pre-alignment of the strands 700 by the notches 518, as shown inFIGS. 22 and 24. The sewing-indexing operation automatically proceedsuntil the strands are sewn in each of the aligned dual passages 514-524by the row of needles 60-2. After the last row of dual grid passages514-524 is sewn, the edge rods 550 have been indexed past the table hole214 so that the pawl 212 contacts the comer bracket 540 as it starts itsupward travel. The bracket 540 prevents the pawl 212 from completing itspredetermined travel thereby causing the switch 210a to stop the machineat the end of the last sewing operation.

6 The strands 700 are secured to the grid box 500 by a U-shaped springclip (not shown) in slots 560; similar to the manner in which thestrands were initially secured to the grid box 500. The strands 700 arethen cut separating the needles 60 and the grid box 500. Thus, thiscompletes the sewing of the grid box in the first of three directions;or in other words, the grid box has strands 700 laced in the Xdirection.

The grid box 500 is turned on the feed table 20 with the complete sewingoperation described hereinabove repeated, thereby completing the sewingof the grid box 500 in the second direction; the grid box 500 now havingstrands also in the Y direction. Again, the box 500 is turned 90 on thefeed table 20 with the operations described hereinabove again repeated,thereby completing the sewing of the grid box 500 in the thirddirection; thus, the grid box 500 now has strands 700 in the X, Y and Zdirections and is capable of use as a three dimensional reinforcement.When the sewing operation is performed when the relationship between thetable and the needle motion is substantially perpendicular then thelattice will be substantially orthogonal.

The amount of prestressing or tensioning of the strands can becontrolled by the force required to pull the strands from their spoolson the creel coupled with the cooperative interaction of the dancer roll704 and the spring tensioned shaft. It has been found that the edge rods550 and the snap rings 543 may be removed after the three dimensionallattice has been sewn and yet the grid box 500 with the grid wallsremain intact.

It is contemplated that more than one set of needles mounted on morethan one reciprocating needle mount can be assembled on the machine sothat sewing in the X, Y and Z directions can be performed continuously,as shown in FIG. 23, wherein machines I, II and III represent theneedles on reciprocating needle mounts, and will be understood by thoseskilled in the art.

The grid box 500 can be any desired configuration as long as the edgerods 550 define exterior surfaces that are substantially planar forminga box such as a parallelepiped. Since the grid surface openings can bemade any desired cross directional configuration, needlesv having asimilar cross sectional configuration can be used therewith. It is alsocontemplated that the needles can sew one or more strands, as desired.It has been found that any type of strand material may be used as longas it is sufficiently flexible for the size of the needles and the sizeof the grid box used. It is also contemplated that the strand materialand different sizes of strands may be mixed while sewing the grid in onedirection; or, alternatively, the strands in one direction can be ofdifferent size and material than the strands in any other direction.

Although specific embodiments of the invention have been described, manymodifications and changes may be made in the machine and the companiongrid structure without departing from the spirit and scope of theinvention as defined in the appended claims.

I claim:

l. A machine capable of using a three dimensional grid structure toarrange strands into a preselected three dimensional lattice array,comprising:

a. a frame having a grid structure support;

b. transporting means for moving the grid structure in a preselectedseries of cycles, each cycle comprising a' move period and a dwellperiod, the transporting means being mounted on the frame;

c. introducing means for feeding multiple strands into the gridstructure to form a three dimensional lattice array, the introducingmeans being mounted on the frame;

d. reciprocating means for reciprocating the intro ducing means relativeto the support during the transporting means dwell period; and

e. strand tensioning means mounted on the reciprocating means.

2. The machine of claim 1 wherein the reciprocating means are slidablymounted on the frame.

3. The machine of claim 1 wherein the introducing means includeslocating means for positioning the strands to be hooked to the gridstructure.

4. The machine of claim 1 wherein the transporting means comprises aneccentrically moving cam actuated pawl.

5. The machine of claim 1 furtherincluding means for sewing strands insubstantially three orthogonal directions.

6. A machine capable of using a three dimensional grid structure toarrange strands into a preselected three dimensional lattice array,comprising:

a. a frame having a grid structure support;

b. transporting means for moving the grid structure in a preselectedseries of cycles, each cyle comprising a move period and a dwell period,the transporting means being mounted on the frame;

0. introducing means for feeding multiple strands into the gridstructure to form a three dimensional lattice array, the introducingmeans being mounted on the frame;

d. reciprocating means for reciprocating the introducing means relativeto the support during the transporting means dwell period; and

e. a plurality of needles whose proximal ends are attached to thereciprocating means, each needle being adapted to sew a plurality ofstrands and having a distal end with a hole and a slot spaced apart byan undercut section.

7. The machine of claim 6 further including equal tensioning means forsubstantially equalizing the tension of all strands.

8. The machine of claim 7 wherein the equal tensioning means includes aspring loaded dancer roll.

9. A machine capable of using a three dimensional grid structure toarrange strands into a preselected three dimensional lattice array,comprising:

a. a frame having a grid structure support;

b. introducing means for feeding multiple strands into the gridstructure to form a three dimensional lattice array, the introducingmeans being mounted on the frame;

0. transporting means for moving the introducing means relative to thegrid structure in a preselected series of cycles, each cycle comprisinga move period and a dwell period;

(1. reciprocating means for reciprocating the introducing means relativeto the support during the transporting means dwell period; and

e. strand tensioning means mounted on the reciprocating means.

10. The machine of claim 9 wherein the reciprocating means are slidablymounted.

11. The machine of claim 9 wherein the strand tensioning means includesa spring loaded dancer roll.

12. The machine of claim 9 wherein the proximal end with a hole and aslot spaced apart by an undercut section.

15. A machine capable of lacing strands comprising: a. a frame; b.holding means mounted on the frame for holding a three dimensional arrayof strands, theholding means comprising grid wall surfaces spaced toform a hollow grid box; and

0. means mounted on the frame for introducing the strands into theholding means.

16. The machine of claim 15 wherein the introducing means are movable.

17. The machine of claim 16 further including means mounted on the framefor transporting the grid box in a preselected repetitive cycle of moveand dwell periods.

18. The machine of claim 17 wherein the introducing means includes meansfor providing reciprocating motion during the dwell periods.

19. The machine of claim 18 wherein the reciprocating means are slidablymounted on the frame.

20. The machine of claim 18 including strand tensioning means mounted onthe reciprocating means.

21. The machine of claim 20 wherein the strand tensioning means includesa spring loaded dancer roll.

22.. The machine of claim 18 including means for positioning the strandswith respect to the grid box.

23. The machine of claim 22 wherein the positioning means includes aplurality of needles.

24. The machine of claim 23 wherein the proximal ends of the needles areattached to the reciprocating means.

25. The machine of claim 24 wherein each needle is adapted to sew aplurality of strands.

26. The machine of claim 25 wherein the distal end of each needle has ahole and a slot spaced apart by an undercut section, the hole and slotadapted to receive a strand.

27. The machine of claim 15 including means for.

providing substantially equal tension in all strands.

28. The machine of claim 15 wherein at least one grid wall has notchesfor aligning the strands.

29. The machine of claim 15 wherein at least one grid wall has means forhooking the strands.

30. The machine of claim 29 wherein the hooking means comprise a lugwith ears.

1. A machine capable of using a three dimensional grid structure toarrange strands into a preselected three dimensional lattice array,comprising: a. a frame having a grid structure support; b. transportingmeans for moving the grid structure in a preselected series of cycles,each cycle comprising a move period and a dwell period, the transportingmeans being mounted on the frame; c. introducing means for feedingmultiple strands into the grid structure to form a three dimensionallattice array, the introducing means being mounted on the frame; d.reciprocating means for reciprocating the introducing means relative tothe support during the transporting means'' dwell period; and e. strandtensioning means mounted on the reciprocating means.
 2. The machine ofclaim 1 wherein the reciprocating means are slidably mounted on theframe.
 3. The machine of claim 1 wherein the introducing means includeslocating means for positioning the strands to be hooked to the gridstructure.
 4. The machine of claim 1 wherein the transporting meanscomprises an eccentrically moving cam actuated pawl.
 5. The machine ofclaim 1 further including means for sewing strands in substantiallythree orthogonal directions.
 6. A machine capable of using a threedimensional grid structure to arrange strands into a preselected threedimensional lattice array, comprising: a. a frame having a gridstructure support; b. transporting means for moving the grid structurein a preselected series of cycles, each cyle comprising a move periodand a dwell period, the transporting means being mounted on the frame;c. introducing means for feeding multiple strands into the gridstructure to form a three dimensional lattice array, the Introducingmeans being mounted on the frame; d. reciprocating means forreciprocating the introducing means relative to the support during thetransporting means'' dwell period; and e. a plurality of needles whoseproximal ends are attached to the reciprocating means, each needle beingadapted to sew a plurality of strands and having a distal end with ahole and a slot spaced apart by an undercut section.
 7. The machine ofclaim 6 further including equal tensioning means for substantiallyequalizing the tension of all strands.
 8. The machine of claim 7 whereinthe equal tensioning means includes a spring loaded dancer roll.
 9. Amachine capable of using a three dimensional grid structure to arrangestrands into a preselected three dimensional lattice array, comprising:a. a frame having a grid structure support; b. introducing means forfeeding multiple strands into the grid structure to form a threedimensional lattice array, the introducing means being mounted on theframe; c. transporting means for moving the introducing means relativeto the grid structure in a preselected series of cycles, each cyclecomprising a move period and a dwell period; d. reciprocating means forreciprocating the introducing means relative to the support during thetransporting means'' dwell period; and e. strand tensioning meansmounted on the reciprocating means.
 10. The machine of claim 9 whereinthe reciprocating means are slidably mounted.
 11. The machine of claim 9wherein the strand tensioning means includes a spring loaded dancerroll.
 12. The machine of claim 9 wherein the proximal ends of aplurality of needles are attached to the reciprocating means.
 13. Themachine of claim 12 wherein each needle is adapted to sew a plurality ofstrands.
 14. The machine of claim 9 further including a plurality ofneedles whose proximal ends are attached to the reciprocating means,each needle having a distal end with a hole and a slot spaced apart byan undercut section.
 15. A machine capable of lacing strands comprising:a. a frame; b. holding means mounted on the frame for holding a threedimensional array of strands, the holding means comprising grid wallsurfaces spaced to form a hollow grid box; and c. means mounted on theframe for introducing the strands into the holding means.
 16. Themachine of claim 15 wherein the introducing means are movable.
 17. Themachine of claim 16 further including means mounted on the frame fortransporting the grid box in a preselected repetitive cycle of move anddwell periods.
 18. The machine of claim 17 wherein the introducing meansincludes means for providing reciprocating motion during the dwellperiods.
 19. The machine of claim 18 wherein the reciprocating means areslidably mounted on the frame.
 20. The machine of claim 18 includingstrand tensioning means mounted on the reciprocating means.
 21. Themachine of claim 20 wherein the strand tensioning means includes aspring loaded dancer roll. 22.. The machine of claim 18 including meansfor positioning the strands with respect to the grid box.
 23. Themachine of claim 22 wherein the positioning means includes a pluralityof needles.
 24. The machine of claim 23 wherein the proximal ends of theneedles are attached to the reciprocating means.
 25. The machine ofclaim 24 wherein each needle is adapted to sew a plurality of strands.26. The machine of claim 25 wherein the distal end of each needle has ahole and a slot spaced apart by an undercut section, the hole and slotadapted to receive a strand.
 27. The machine of claim 15 including meansfor providing substantially equal tension in all strands.
 28. Themachine of claim 15 wherein at least one grid wall has notches foraligning the strands.
 29. The machine of claim 15 wherein at least onegrid wall has means for hooking the strands.
 30. The machine of claim 29wherein the hooking means Comprise a lug with ears.